Nutrition and Depression
Most drugs used to treat mental health disorders act on the chemicals in the brain to alter these and return the brain to a healthy state: some increase these chemicals, and some decrease them. For example, serotonin is one of the most commonly manipulated with selective serotonin uptake inhibitors or SSRIs, which boost serotonin levels as a treatment for depression.
Did you know that you can also boost serotonin levels with specific foods?
This article will delve into what is known regarding nutrition and depression - what to eat, what to avoid, and how food can improve the brain. Diet, in addition to medication (or possibly instead of in some cases), provides another option for this common disorder.
Depression in youth has escalated
In 2020, in the U.S., it was estimated that 21 million adults, or 8.4%, had at least one major depressive episode; ages 18-29 have the highest prevalence.
The number of adolescents that year was estimated at 4.1 million or 17% of those 12-17. 41% of these received treatment.
Teen girls are three times as likely as boys to suffer depression.
In one decade, from 2007 to 2017, the number of teenagers who experienced depression increased by 59%. This increased further during COVID 19.
Suicide is the 3rd leading cause of death for ages 5-19, and psychiatric disorders are a risk factor.
Major depression is one of the most common mental disorders. Research is looking at diet more and more as a treatment option.
The brain affects the gut and the gut affects the brain, as depicted in this schematic
The Mind-Gut-Depression Connection
The gut bacteria make many chemicals with action in the brain. Various neurotransmitters - dopamine, serotonin, and gamma-aminobutyric acid (GABA) - are included. The balance of bacteria within the gut affects the balance of the chemicals made. This balance is influenced by diet. The gut microbiome can also affect the amount of inflammation in the body and brain that affects our overall health. Gut bacteria that cause inflammation are found in higher concentrations in those with depression.
Psychological stress also affects the balance of the gut microbiome, resulting in lower levels of good bacteria, with fewer available for protective function. An unhealthy gut microbiome can lead to an unhealthy brain. Depressed individuals are shown to have disruptions in their gut bacteria compared to those without depression. Food has the most impact on the brain by impacting the gut microbiome. Diet can help or harm our mental state.
Nutrients with Ties to Depression
It is difficult to improve your mood with unhealthy food. Nutrients that may be helpful based on research are below.
Two B vitamins - B9 (folate) and B12 (cobalamin), are linked to depressive symptoms when low. Depression is a common symptom of folate deficiency.
Folate can be obtained from legumes, nuts, dark green vegetables, and many fruits.
Cobalamin is in low-fat animal products such as fish, low-fat dairy, lean red meat, eggs, and poultry.
Vitamin D is another vitamin in which decreased levels have been tied to an increased risk for depression, especially seasonal depression. Fatty fish, like salmon and tuna, egg yolks, mushrooms, vitamin D-fortified milk, orange juice, and cereals are all great sources. This vitamin may need to be supplemented for children who don’t consume dairy or are picky eaters.
Low selenium has been linked to poor moods and can be found in beans and legumes, lean meats, whole grains, low-fat dairy, seafood, nuts, and seeds.
Iron is another mineral that affects brain function and mood. Sources include red meats, organ meats, shellfish, legumes, dark leafy greens, and pumpkin seeds.
Magnesium deficiency has been connected to depression and, if deficient and supplemented, can improve depressive symptoms. Get this from avocados, legumes, whole grains, fatty fish, nuts, and seeds.
Higher rates of depressive disorder have been found in those who don’t consume enough omega-3 fatty acids. These are so important to brain function and protect the brain from inflammation. Patients with depression have been found to benefit from omega-3 fatty acids. Sources include fatty fish (the best source), flaxseed, some cooking oils, nuts (especially walnuts), grass-fed meats, and dark green leafy vegetables.
Tryptophan is an essential amino acid from which serotonin is made. Serotonin does not exist in foods, but tryptophan does. Tryptophan-rich foods include turkey, chicken, and tuna. Additional foods include milk, cheese, oats, lentils, nuts, and seeds.
Foods with tryptophan that can boost serotonin levels
Antioxidants, including vitamins A (beta-carotene), C, and E, fight free radicals in the brain that can cause damage. Vitamins A and C are easy to obtain from citrus fruits, orange and yellow vegetables, broccoli, spinach, tomatoes, peppers, potatoes, and berries. Vitamin E is found in nuts and seeds, vegetable oils, and wheat germ.
Carbohydrates have been linked to serotonin levels but choose your carbs wisely. Opt for whole-wheat and whole-grain carbs (complex carbs) over refined ones (simple carbs). Choose vegetables, fruits, and legumes as sources of carbs with fiber.
Many spices are also known for their antioxidant benefits. These include turmeric, oregano, and saffron.
Just last month a study reported changes in the gut microbiome associated with depression. The researchers suggested that patients suffering from this should be advised to modify their diet to provide the gut with the fiber needed to change the fatty acids in the gut. This entails increasing fresh fruits, vegetables, and whole grains, while minimizing intake of sugar and processed foods.
Probiotics and Prebiotics help build a healthy gut microbiome
Probiotics and prebiotics can affect the makeup of the gut microbiome. Probiotics are found in yogurt containing live cultures (avoid those with added sugar), fermented foods (kimchi, pickles, sauerkraut, kefir, kombucha, miso, tempeh, buttermilk), and in supplements. Prebiotics act as food for the gut bacteria and come from high-fiber foods such as cruciferous vegetables (those with a stalk - asparagus, artichokes, broccoli, brussels sprouts, cabbage, leeks), beans and legumes, garlic, onions, and oats.
What to Avoid
High sugar intake can worsen depression by acting on the gut microbiome. Research has revealed that high sugar consumption increases depression risk. Too much sugar in the brain, especially from sugar-sweetened beverages and processed foods, increases inflammation in the brain. This, in turn, leads to lower levels of brain-derived neurotrophic factor (BDNF) which helps the brain adapt to stress. Remember that sugar also comes from refined carbohydrates, even though these may not taste sweet. Look for bread, pasta, crackers, etc., made from whole wheat and whole grains.
Artificial sweeteners (see the post from 3/1/23 on these), especially aspartame (NutraSweet), has been linked to depressive symptoms. These are in so many foods but especially in diet drinks. Aspartame is the one most linked to depression by inhibiting the release of certain neurotransmitters such as serotonin and dopamine.
Fried foods and unhealthy fats (saturated fats) may increase depression risk. In contrast, increased intake of polyunsaturated and monounsaturated fats (PUFAs and MUFAs) can help guard against depression. MUFAs from nuts, nut butter, olive oil, and avocados are all healthy fats.
Nitrates are a preservative and color enhancer in cured and processed meats. These can also alter the gut microbiome. Nitrates are in salami, sausage, bacon, pepperoni, and lunch meats.
The Mediterranean diet or eating pattern, predominantly plant-based, has been promoted by the International Society for Nutritional Psychiatric Research as a diet to nurture brain function, regulate mood, and protect against depression. As written in previous posts, it is also healthy for the heart and gut microbiome. It provides a nutrient-dense diet that benefits the body and the brain. The Nordic and Japanese diets are also eating patterns that are promoted to improve depressive symptoms.
Focus on healthy eating, from the beginning, as a potential preventive measure against mental health disorders. Diet is also a way to improve symptoms or boost the effects of medication. The mind and the body will both benefit!